Saturday, February 20, 2010

14 Ari and Albategnius captured (Toronto)

Bound and determined, after all this gloomy talk, I felt that I had no excuse for not observing tonight. Well, aside from the mountain of paper work to catch up on, preparations for upcoming training work, interesting movies on TVO. No, really! In fact, one was Apollo 13 by Ronnie Howard. Man, that flick always makes me feel cold. So I set about making a plan for the evening. Not too ambitious but still with some serious astronomical objectives:
  • accurately measure a double star, 14 Arietis, with the CMG
  • view and sketch Mars
  • photograph Mars with a "special new technique"
  • first practice the new technique on the Moon
With some challenge items:
  • split α (alpha) Piscium, a very tight double star
  • view Vesta, shortly after opposition, naked eye
In addition to my usual sources of information, I took a look at CalSky and Tonight’s Sky. Weather tools suggested pretty good conditions although the CSC transparency ratings did not look great. And the Moon was nearing first quarter, so, unless there were some stunning globular or open clusters, I wasn’t going to aim for DSOs. I was in red light mode before dinner and ready to go around 7.

I remembered to check the latitude setting on the mount. Looked OK. I made a small adjustment, in hopes of eliminating the slight drift I saw before...

At around 7:30, I caught sight of a satellite. I picked it up in the west about 45° up. To the right of the Moon and heading to the zenith. It went through Perseus. It was not as bright as Mirphak (1.75) but about the same as δ (delta) Persei (3.00), definitely not the level of Capella (0.05). It remained steady, this slow mover, as it moved into Ursa Major (near the brightness of Dubhe and Merak, 2.00 and 2.30, respectively). Lost it in the neighbour’s tree at 7:34. So maybe magnitude 3? Funny, I wasn’t really expecting that. In fact, I had dismissed all the satellite flyovers suggested by CalSky.

Re-reading the CalSky list, it looks like I saw the USA 182/Lacrosse 5. They say it was to appear at 19h23m with a 7.3 mag at azimuth 231° SW on the horizon. It was to culminate at 19h30m with a 2.6 mag at an elevation of 75.2°. And finally, it was to disappear at 19h34m, 3.9 mag, az 42.6° NE, h 20.5°. Sounds right. As I watched it and considered its speed, and how long it stayed in the sunlight, the time some 2 hours after sunset, I wondered if it was higher than the ISS. CalSky says it is, over 700 km up.

Huh. Struck by a crazy idea. With Vesta on my plan and seeing Juno was near Pisces, I thought, hey, I should view several asteroids tonight! So I started starhopping to Juno. Had to make a couple of trips into “the warm room” to verify the location. By then, I had all the necessary gear outside.

7:52. I noticed the low battery indicator again on the Oregon Scientific portable weather station. Once more, it does not like the cold. Or rather, these lithium batteries do not like the cold. I glanced at the temperature and noted 0.3°. But I forgot to check if that was minus. That said, I knew it was still acclimating to being outside.

Before departing from a Psc, I cranked up the magnification. And enjoyed the remarkably tight double again. So tight that the general appearance was a figure 8. Only briefly did they completely separate. I detected colour this time! The main star I thought white-blue; the companion burnt orange. The second star was only slightly dimmer. That sucker must be luminous though, still close to the main star in magnitude, to let me detect hue. Very interesting. I visually estimated the Position Angle to be 275°. Haas says separation is 1.9”, the magnitudes are 4.1 and 5.2, and the PA was 270 (noted in 2004).

My back was cold! Perhaps the light wind? Switched to a warmer coat.

Continued my starhopping to Juno. At 8:13, I did a sketch of the field of view in the Plössl. The humidity was 60% and the temp was -0.5°.

The drawing is inconclusive. I noted the star between HP 9557 and where (3) Juno should be. That’s a mag 11.00 star! And yet I did not see the mag 10.95 star near 9579? Nor the 10.55 star near Juno? Was it the low elevation? 23° up? I was going through lots of air... Too bad I could not have followed it for another hour. See which of those “stars” moved. Anyway, I was certainly in the area!

[ed: I reviewed this sketch against the charts in SkyTools3 and I believe the bright point on the left is the asteroid. It would have been useful to return in one hour... It was moving pretty fast!]

For the next hour, I calibrated the Linear Scale of the Celestron MicroGuide eyepiece. I chose ι (iota) Cassiopeiae. Apropos, the lovely triple! Quickly estimated the PAs to be 100 and 225; not bad: 115 and 230 according to Haas. First couple of calibration times I had to toss out—no 2x Barlow in place. Oops. Captured 7 good times using my palmtop Stopwatch program’s lap timer. Not just for race tracks.

Polar alignment was still off...

Checked the conditions at 9:14: 66% and -1.3°. Ugh. My target star was getting low. Only 30° up. That would affect seeing…

It was an easy starhop from Hamal to 14 Aries. I found a wide pair, pale yellow and pale blue. I measured the sep and PA. I captured the initial exit angle on the large circular scale. I noted the number of ticks apart on the linear scale. And then I performed Teague’s “advanced” method and captured the two “tilt” angles. All for later reduction.

While viewing the bright star in 14 Aries, with the 12.5mm eyepiece, I clearly saw diffraction rings. But, sadly, they were not uniform. There's no doubt now. Time to collimate.

I headed to Mars. And was shocked. The transparency was very good with the Meade 18mm. And then improved with the Barlow. I could see a ton of detail at 222x! The polar cap seemed very large, quite white. Immediately below it was a pronounced dark region with a triangular point (I learned latter was Utopia). The south pole was mostly dark slate blue. There was Syrtis Major again, to the right of the meridian (mirror reversed). But I could vaguely see detail in the pale orange regions between the north and south poles, hints of lines and streaks. Astounding. The view seemed to degrade slowly. Either that or I was getting tired.

I had my clipboard, various pencils, Pink Pearl eraser, red flashlight, and large log sheet ready to go. But as I tried to sketch, I found it… just awkward. I realised that my custom log sheet with the 16 cm circle was too big! This is OK for clusters or nebula or moons orbiting a planet. I remembered a web site where the author suggested sketching planets in pre-drawn circles. I ran inside for my older log sheets. This earlier edition featured small log reports, each with small circle, 1/4 the size of this large one. Much better. Then I grabbed my baseball cap clip light, the hacked version with red LEDs, I needed to free up a hand. But as I put the light on the bill, one of the two clips snapped. Crap!

Well, maybe that’s just a sign… An MEC head lamp (like the one I gave Mom) may be in my future.

Back outside, fumbling with lights and pencils, I completed a sketch of Mars. It was 10:07. I didn’t spend a lot of time at it but was pleased with the result overall. And I used the eraser to fix something! That was a first. When I compared it to the Mars Profiler from Sky & Telescope, I’m amazed. If I keep up at this, keep practicing, keep slowing down, I might get pretty good at this…

[ed. sketch coming soon]

I was intrigued by the sharp angle, the 90° bend between Syrtis Major and Mare Tyrrhenum, the light orange area of Libya. I also noted the gradually angling up of the dark region from the bottom left, Mare Cimmerium, toward Libya.

OK. Time for photos! First stop: Luna. I put the telescope on the Moon and inserted the 26mm Plössl.

The plan was to try the trick I had read about, in a couple of places, on the web. It was suggested that for a point-and-shoot camera used afocally with a telescope, you needed to get the light rays from the eyepiece emerging in a parallel pattern, not a converging one for the eye. So I grabbed my cheapo binos and viewed the Moon focusing the Bushnells crisply on the Moon. Then I looked down the eyepiece with the binos. Wow, huge! Very close up! But it made it easy to focus. I adjusted the telescope until it was good through the binoculars. That was pretty easy.

I bolted up the eyepiece-camera adapter (on loan from the RASC). Aligned the J20 camera, powered it up, and saw a good image! I max’ed the optical zoom and found the view very impressive. Shot photos from 10:18 to 10:22 adjusting the ISO from 100 to 400 and 800. I’m astonished with the results.

FujiFilm finepix J20, SP-C8, Celestron 26mm Plossl EP, eyepiece-camera clamp
1/17 sec, camera focal ratio f5.6, focal length 19mm, ISO 800
edited in Fireworks: scaled to 1/3rd, sharpened, flipped vertically, rotated, auto levels

In Virtual Moon Atlas, I identified the area. The photo is nearly centred on Albategnius with most of the crater in shadow save the centre peak just visible. Just peeking into the sunlight.

I wanted to try the same “parallel rays” technique for Mars. The photos did not come out well though. Oh well. The Moon ones make up for it! It is incredible that I can see craters down to 10 km in diameter.

I was feeling tired, a little anxious about tomorrow, and thinking I should not stay up late. Got lots done though. I packed up quickly in the garage again, not breaking down the ‘scope, just moving it inside the garage. It was great tonight being up to go outside and use it in minutes.

Done. 10:46. It was -2° at 70% humidity.


Indoors, I uncloaked and readied for bed. But I really wanted to see what I had accomplished with my double star measurement! No time for the whole blog but I could quickly crunch the numbers.

I exported the calibration times from the Psion Stopwatch program. I then pulled these into a Psion Word document, cleaned the data, and then copied the good times to a Psion Sheet. I parsed the text then averaged the numeric times: 42.97 seconds to travel along the centre linear scale of the CGM. I visually estimated the stars separated by 25.5 ticks. I punched these numbers, along with the declination of ι Cas, into my palmtop spreadsheet. It returned a separation of 105.4”.

It was at this point that something occurred to me. That when one measures the exit angle during the drift process, the reticule can be oriented two ways! While the centre linear scale numbers aren’t a factor, the zero value can either be near to or far from the main star in the double system. Which way? That means the exit angle could be off by 180°! Oh oh.

I punched the exit, tilt 1, and tilt 2 numbers into the spreadsheet and got crazy PA and sep numbers. I examined the reticule, turned it 180°, inferred a new set of numbers. Put these in the spreadsheet. Ah ha! That’s more like it. Based on Teague’s “advanced” method, I get sep 103.9” and PA 281°.

I re-read Teague's article and I found it, an almost side comment, at the end of a paragraph, that said one must put the zero mark near to the main star. Ah. Missed that comment. I'll need to add that to my notes...

In all of this, while comparing against the numbers in Sissy Haas’s book, I learned that 14 Aries is a triple star! Oh. And the AB and AC stars have about the same sep and mag! Well, then. I only measured stuff between what I thought were the two bright stars in the area. So, it seems that I measured the “AC” pair. Haas reports the 2003 sep of 106.7” and PA 278°.

So, I'm in the ball park, which is good. But it is interesting how different they still are from each other and Haas.


Had a funny thought during the session. Involving multi-night observing, storing the assembled telescope quickly in the garage, having access to a warm room. In particular, I was thinking about summer evenings where the enemy is dew. A couple of times last year, I used the picnic table with the umbrella opened. Works but it’s still a bit limited. The neat idea that popped into my head was to use the garage itself! I’m already kicking out the car to make it easy to move the ‘scope. So, I’ll have to remember this for the future. A couple of tables, I’ll be good to go! Just need to watch the trip hazards. And maybe mute the red light. It’ll be fun to try.

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